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University of Plymouth PEARL https://pearl.plymouth.ac.uk 04 University of Plymouth Research Theses 01 Research Theses Main Collection 2015 Palaeoecology of the late Permian mass extinction and subsequent recovery Foster, William J. http://hdl.handle.net/10026.1/5467 Plymouth University All content in PEARL is protected by copyright law. Author manuscripts are made available in accordance with publisher policies. Please cite only the published version using the details provided on the item record or document. In the absence of an open licence (e.g. Creative Commons), permissions for further reuse of content should be sought from the publisher or author. Appendix 2.1: Balaton Highlands and Bükk Mountains Investigated sites. The Permian-Triassic succession of Balaton Highlands comprises part of the ALCAPA megaunit (Kóvacs and Haas, 2010) and is represented by Permian fluvial red sandstones and Triassic shallow marine rocks. The Lower Triassic succession in the Balaton Highlands is divided into four formations: the Kóveskál Dolomite Formation, Arács Marl Formation, Hidegkút Formation and Csopak Marl Formation (Figure A2.1). These formations paraconformably overlay the Permian Baltonfelvidék Formation and are capped by the Middle Triassic Aszòfo Dolomite Formation (Haas et al., 2012). Field visits (June 2012) to the Balaton Highlands (Figure A2.2) recorded 5m of the Kóveskál Formation at Balatonfüred; 15m at Balataonálmadi; and 1m of the Csopak Marl Formation at the Sóly section. Broglio Loriga et al. (1990) studied the biostratigraphy of the entire succession, but their data, were acquired from a trench that is no longer exposed (János Haas, pers. comm.) and their collections were not available for study (Renato Posenato, pers. comm.). The Bükk Mountains succession is composed of very low-grade metamorphosed, shallow marine Upper Permian and deep marine Lower Triassic deposits and belongs to the sheared MHMU (Haas et al., 2006). The Lower Triassic succession is represented by the Gerennavár Limestone Formation and Ablakoskővölgy Formation (Figure A2.1). These conformably overly the Changhsingian Nagyvisnyó Limestone Formation (Haas et al., 2006; Sudar et al., 2008) and are overlain by the Middle Triassic Hámor Dolomite Formation (Figure A2.1). In the Bükk Mountains exposures of undeformed Lower Triassic strata are limited to the well-studied 4m thick Bálvány-North section; the 8m thick Bálvány-East section; and an inaccessible 40m section at Gerennavár (Figure A2.3). The 250m road-cut section at Lillafüred is tectonically deformed, thus unsuitable for investigation (Hips and Pelikán, 2002; Figure A2.3). -333- Figure A2.1: Formation subdivision of the Lower Triassic sequences of Hungary in the Balaton Highlands (after Haas et al., 2012), Bükk Mountains (after Haas et al., 2007) and Aggtelek-Rudabanya Mountains (after Hips, 1998). Vertical blank lines indicate an unconformity. -334- Figure A2.2: Locality maps of the study sites in Balaton Highlands Range. A) The Transdanubian Mountain Range showing the surface extent of the Triassic formations (after Haas and Budai, 1999). B) Balatonfüred road-cut. C) Balatonalmádi. D) Sóly. Figure A2.3: Locality maps of the study sites in the Bükk Mountains. B) Study site locations within the Bükk National Park. C) Permian/Triassic boundary sections: Bálvány-North, Bálvány-East and Gerennavár. D) Lillafüred. -335- Appendix 2.2: Polished slab taxonomy Polished slab taxonomy Specimens that could be confidently identified on bedding surfaces of carbonate and sandstone beds were cut along the transverse and sagittal plane to reveal information on the shell shape, thickness, composition and ornamentation when viewed in cross- section. These features were then used to discriminate between different taxa observed in the polished slab samples (Table A2.1). Sections of fossils that were only observed in polished slab and not on bedding planes, at best, were only identifiable to genus-level, e.g. Microconchus, based on observations of thin sections in previous Lower Triassic studies (Table 1). Shell fragments observed in the polished slabs were identified as such and not included in the analysis. Using the polished technique does include some uncertainty as discriminating between some species is not possible from a two-dimensional view, e.g. cf. Unionites fassaensis and cf. Unionites canalensis. The specimens identified from the polished slab technique were, therefore, identified to the lowest taxonomic level to which they could be confidently assigned, e.g. Unionites only identified to genus-level in this study. -336- Table A2.1: Classification of benthic fossil invertebrates in polished section from the Lower Triassic of the Aggtelek Karst. Polished slab Description Remarks Bivalve sp. A Thin, slightly convex bivalve shell with This bivalve was not observed in the reference material, and bivalves with irregular spaced, large acute ribs. The ribs large irregular spaced acute ribs are currently unreported from the Lower are loosely packed along the shell. Triassic of central Europe. Bivalve sp. B Thin, moderately convex, smooth bivalve This bivalve morphology is similar to N. ovatus (see below), except that the shell. The bivalve shell has three layers thickness of the outer layers of the shell is thicker. with the middle layer being the thickest. Bivalve sp. C Thin, moderately convex bivalve shell This bivalve morphology is similar to Eurmophotis. The presence of acute ribs, with densely packed acute ribs. however, means that the morphology can be distinguished from Eumorphotis. Another genus with densely packed acute ribs is Costatoria, however, Bivalve sp. C occurs in the Tesero Member and Costatoria is not recorded until the Campil Member. In addition, the shell thickness is thinner than observed for Costatoria. -337- Bivalve sp. D A large bivalve shell, highly convex, A reference sample was observed for this morphology, however, due to the smooth, with a slightly variable size. Shell poor preservation this bivalve morphology cannot not be assigned to species, structure consists of a single layer. genus or family-level. This morphology is similar to Unionites, but differs in being more convex and having a single thin shell layer. A Unionites mode of life, therefore, was also interpreted for this morphology. Claraia clarai group Thin bivalve shell, slightly convex, with Indistinguishable from Claraia stachei in polished section but C. stachei has regularly spaced folds. not been recorded from the Aggtelek Karst and all specimens on the surfaces of the polished slab samples were identifiable as C. clarai. These differ from Scythentolium in having visible folds and possessing a thinner shell. Claraia and the Pterinopectinidae possess thin shells with two shell layers: a calcitic outer layer and aragonitic inner layer (Newell and Boyd, 1995; Carter, 1990). In this study, these bivalve shells appear as moulds or casts. Claraia aurita Thin bivalve shell, slightly to moderately In the polished slabs these shells are much larger (up to 30mm) and more convex, with no ornamentation. convex than cf. Unionites. Claraia aurita differs from C. wangi-griesbachi in being significantly larger. This shell morphology is also similar to Eumorphotis, however, in the bulk samples the stratigraphic ranges of C. aurita, C. wangi-griesbachi and Eumorphotis do not overlap. In addition, this shell morphology was only recorded in one polished slab sample that also had C. aurita on the bedding plane. -338- Claraia wangi-griesbachi Thin bivalve shell, slightly to moderately In polished slab C. wangi-griesbachi is indistinguishable from C. aurita. The convex with no ornamentation. ranges of these two species, however, have not been recorded to overlap in Hungary or Italy. This morphology in the Mazzin Member, Italy, is, therefore, assigned to C. wangi-griesbachi and in the Siusi Member to C. aurita. Eumorphotis spp. Thin bivalve shell, slightly to moderately Eumorphotis is a diverse Lower Triassic genus and distinguishing between the convex. Has a three-layered shell structure different species identified in central Europe using polished slabs is not with each layer being a similar thickness. possible. Eumorphotis differs from Bakevellia in lacking a steeply sloping Ornamentation consists of rounded ribs, or anterior margin and from Scythentolium in having a thinner shell. Eumorphotis if the valve is cut along the sagittal planes has been variably placed within the Heteropectinidae (Hofmann et al., 2014), the valve appears smooth. Etheripectinidae (Posenato et al., 2005; Hautmann et al., 2011) and Aviculopectinidae (Carter, 1990; Ros-Franch et al., 2014). The shell structure differs from the calcitic shell structure of the Heteropectinidae figured by Newell and Boyd (1995) and does not resemble any of the variable shell structures of the genera in the Aviculopectinidae (Carter, 1990). The shell structure of the Etheripectinidae has not been described and no comparison is yet possible. Scythentolium sp. Relatively large bivalve shell, smooth, These specimens and reference samples lack ornamentation of S. tirolicum slightly convex with a thick shell divided described by Wittenburg (1908). The smooth morphology and slightly into three layers with a thick middle layer inequilateral shell is more similar to Scythentolium sp. A figured by Hofmann and thinner inner and outer layers. et al. (2015a). The shell structure of entoliids is poorly known (Carter, 1990), and the right and left valves have different microstructures. No differences